It's not working for the guy. It won't work for anyone. Nobody else in the world is better at being John Cena than John Cena. It didn't work when they tried to make Lex Luger the next Hulk Hogan.
Bruno Sammartino was different from Buddy Rogers.
Bob Backlund was different from Bruno Sammartino.
Hulk Hogan was different from Bob Backlund.
They tried to make Lex Luger another Hogan. Didn't work.
Bret Hart and Shawn Michaels were different from Hulk Hogan.
Steven Austin and The Rock were different from Bret Hart and Shawn Michaels.
John Cena is different from Steven Austin and The Rock.
When WWE tried to make a Hogan 2.0 they really just set guys up for failure. And what they're doing with Roman Reigns is just gonna have the same result.